Era
20th century
36
19th century
11
1945-
9
1949-
7
1933-1945
6
1918-1933
5
1939-1945
5
1871-1918
4
1945 -
4
1949
4
1900-
3
1914-1918 - Causes
3
1917-1936
3
1925-
3
1961-1975
3
1976-
3
20th century - Juvenile literature
3
Biography
3
1893-
2
1917-1921
2
1920-1929
2
1925-1953
2
1942 - 1945
2
1942-1949
2
1948-1960
2
1949-1976
2
1950-
2
1959-
2
1966-
2
1975-
2
1976
2
1985-
2
20th century. --
2
Australia
2
Japanese occupation, 1942-1945
2
Republic, 1912-1949
2
United States
2
1478-1798
1
17th century
1
1801-1917
1
1801-1917 - Sources
1
1812-1870 --
1
1819-1975
1
1857-1919
1
1859-1935-
1
1861 -1912
1
1861-1865
1
1866-1953
1
1867-1918
1
1868-
1
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